WO 95/20176 discloses an instrument for automatic deposition of coverslips. The pickup head possesses suction cups, facing outward from the longitudinal axis of the pickup head, to which a vacuum can be applied individually. A piston that is mechanically preloaded downward with a spring is provided between the suction cups. In order to pick up a coverslip, the pickup head is pressed onto the coverslip stack and until the suction cups are in contact with the topmost coverslip. The adhesion between the topmost coverslip and the coverslips below it is overcome by means of a shearing motion. The specimen slides that are to be equipped with coverslips are deposited in a drawer. This does not result in any automation of the apparatus, since the user him- or herself must reload specimen slides.
The automatic stainer and coverslipper are two separate units. According to the existing art, after the staining operation the specimen slides needed to be manually removed from the stainer and inserted into the coverslipper in order to start the process of covering them with coverslips (see Leica brochure CV 5000). Despite the automation of the individual units, manual loading of the coverslipper is necessary. Smooth operation requires that laboratory personnel occupy themselves, at very short intervals of a few minutes, with removing racks from the stainer and loading the coverslipper.